Patent GB-999505-A (GB)
Title: Control means for epicyclic power transmission mechanisms
Inventor: WHATELEY ERIC ALBERT
IPC: F16H3/66
Filed: 1960-10-12
Abstract: 999,505. Friction clutches; change-speed gear. A. C. WICKMAN. Oct. 9, 1961 [Oct. 12, 1960], No. 34894/60. Addition to 961,027. Headings F2C, F2D and F2L. Change-speed planetary gearing for motor cars &c. comprises an arrangement of clutches in which a driving clutch frusto-cone 24 has a pin-and-slot connection 26 with an input shaft 27 and is axially movable by energization of a non-rotary liquid pressure servo 50 acting through a thrust bearing to engage it with a first driven clutch disc 32, a second servo 55 being energized to move a second driven clutch disc 33 axially against spring bias into engagement with the driving clutch cone 24, simultaneously overcoming the servo 50 and sliding the driving cone out of engagement with the first disc 32, the second clutch disc 33 sliding in the opposite direction on energization of a more powerful servo 56 capable of overcoming the servo 55, and ratio establishing clutch discs 40, 47 being engaged by energization of servos 65, 66 so arranged that the servo 65 is always connected through a pipe 77 with the servo 56. First ratio is obtained by energizing the servo 50 to engage the driving clutch cone 24 with the first clutch disc 32, fast with a shaft integral with a sun gear 4 meshing stepped planet pinions 11 in turn meshing a ring gear 19 stationed by a manually controlled pawl 17, the planet pinions being mounted in a carrier fast with a driven shaft 13. Second ratio is obtained by keeping the servo 50 energized while also energizing the second servo 55 to overcome the first servo, thus engaging the second clutch disc 33 with the driving clutch cone 24 and sliding the latter out of engagement with the first clutch disc 32, drive now passing to a larger sun gear 6 also meshing the stepped planet pinions 11. Third ratio is obtained by keeping the servos 50, 55 energized and also energizing the servos 56, 65, 66. The servo 56 acts through a thrust bearing upon a flange 62 carried by a hollow shaft fast with the second clutch disc 33 to move the latter axially overcoming the servo 55, out of engagement with the driving clutch cone 24, which latter re-engages with the first clutch disc 32. Drive is thus once more transmitted to the sun pinion 4. The servos 65, 66 engage the clutch disc 40 with a brake ring 43 to station a reaction sun gear 9 meshing stepped planets, Fig. 2 (not shown), meshing the stepped planets 11. The ring gear 19 now overruns relatively to the pawl 17 by virtue of a one-way detent 22, and the carrier transmits drive to the driven shaft 13. Fourth ratio is established by maintaining the servos 50, 55, 66 energized, and de-energizing the servos 56, 65. The servo 55 is now able to re-engage the second clutch disc 33 with the driving clutch cone 24, and the sun gear 6 transmits drive instead of the sun gear 4. Fifth speed (direct drive) is established by keeping the servos 50, 55, 66 energized and also energizing a servo 73, the latter engaging the clutch discs 40, 47 so that the sun gears 4, 6 rotate solidly, simultaneously overcoming the servo 66 to release the clutch disc 40 from the brake ring 43. To establish reverse, the detent pawl 17 is disengaged from the ring gear 19 and instead engaged with a ring gear 16 meshed by the stepped planets (not shown) meshed by the planets 11, and the servo 50 is energized so that drive is transmitted to the sun gear 4.